"Some parts of Oklahoma now match Northern California for the nation’s
most shake-prone," writes Doug Stanglin of USA Today, "and one Oklahoma region has a one-in-eight chance of a
damaging quake in 2016, with other parts closer to one in 20."

NBC News reports that this morning's quake was centered in north-central
Oklahoma near Pawnee, on the fringe of an area where regulators had stepped in to
limit wastewater disposal.